English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We study the Kennicutt-Schmidt relation between average star formation rateand average cold gas surface density in the Hi dominated ISM of nearby spiraland dwarf irregular galaxies. We divide the galaxies into grid cells varyingfrom sub-kpc to tens of kpc in size. Grid-cell measurements of low SFRs usingH-alpha emission can be biased and scatter may be introduced because ofnon-uniform sampling of the IMF or because of stochastically varying starformation. In order to alleviate these issues, we use far-ultraviolet emissionto trace SFR, and we sum up the fluxes from different bins with the same gassurface density to calculate the average $\Sigma_{SFR}$ at a given value of$\Sigma_{gas}$. We study the resulting Kennicutt-Schmidt relation in 400 pc, 1kpc and 10 kpc scale grids in nearby massive spirals and in 400 pc scale gridsin nearby faint dwarf irregulars. We find a relation with a power law slope of1.5 in the HI-dominated regions for both kinds of galaxies. The relation isoffset towards longer gas consumption timescales compared to the molecularhydrogen dominated centres of spirals, but the offset is an order-of-magnitudeless than that quoted by earlier studies. Our results lead to the surprisingconclusion that conversion of gas to stars is independent of metallicity in theHI dominated regions of star-forming galaxies. Our observed relations arebetter fit by a model of star formation based on thermal and hydrostaticequilibrium in the ISM, in which feedback driven turbulence sets the thermalpressure.

The spatially resolved Kennicutt-Schmidt relation in the HI dominated regions of spiral and dwarf irregular galaxies